Environmental and financial impacts of perioperative paracetamol use: a multicentre international life-cycle analysis.

BACKGROUND: Pharmaceuticals account for 19-32% of healthcare greenhouse gas (GHG) emissions. Paracetamol is a common perioperative analgesic agent. We estimated GHG emissions associated with i.v. and oral formulations of paracetamol used in the perioperative period. METHODS: Life-cycle assessment of GHG emissions (expressed as carbon dioxide equivalents CO2e) of i.v. and oral paracetamol preparations was performed. Perioperative paracetamol prescribing practices and costs for 26 hospitals in USA, UK, and Australia were retrospectively audited. For those surgical patients for whom oral formulations were indicated, CO2e and costs of actual prescribing practices for i.v. or oral doses were compared with optimal oral prescribing. RESULTS: The carbon footprint for a 1 g dose was 38 g CO2e (oral tablet), 151 g CO2e (oral liquid), and 310-628 g CO2e (i.v. dependent on type of packaging and administration supplies). Of the eligible USA patients, 37% received paracetamol (67% was i.v.). Of the eligible UK patients, 85% received paracetamol (80% was i.v.). Of the eligible Australian patients, 66% received paracetamol (70% was i.v.). If the emissions mitigation opportunity from substituting oral tablets for i.v. paracetamol is extrapolated to USA, UK, and Australia elective surgical encounters in 2019, ∼5.7 kt CO2e could have been avoided and would save 98.3% of financial costs. CONCLUSIONS: Intravenous paracetamol has 12-fold greater life-cycle carbon emissions than the oral tablet form. Glass vials have higher greenhouse gas emissions than plastic vials. Intravenous administration should be reserved for cases in which oral formulations are not feasible.

Prediction, prognosis, and professionalism in perioperative medicine.

Guidelines provide a framework to take better care of our patients. They are published by different professional groups and are based on all the research done for us by hardworking colleagues. Compiling a guideline is an enormous amount of work and is generally done with the utmost care. However, recommendations often require a subjective interpretation of published research, where personal and academic interests can influence the outcome. We discuss two recently published guidelines on perioperative cardiovascular assessment that led to different conclusions on some important areas of patient care.

Reducing the time to activation of the emergency call system in operating theatres: effect of installing vertical red line indicators.

BACKGROUND: The 7th National Audit Project of the Royal College of Anaesthetists (NAP7) recommended that an emergency call system be immediately accessible in all anaesthesia locations. It is essential that all theatre team members can rapidly call for help to reduce the risk of patient harm. However, the ability of staff to activate this system in a timely manner can be affected by cluttered or unfamiliar environments and cognitive overload. One proposed strategy to enable rapid identification and activation of emergency call systems is to install a red vertical painted stripe on the wall from the ceiling to the activation button. We investigated the effect of introducing this vertical red line on activation times in operating theatres in the UK and Australia. METHODS: Operating theatre team members, including anaesthetists, surgeons, anaesthetic nurses, surgical and theatre nurses, operating theatre practitioners, and technicians, were approached without prior warning and asked to simulate activation of an emergency call. Vertical red lines were installed, and data collection repeated in the same operating theatres 4-12 months later. RESULTS: After installation of vertical red lines, the proportion of activations taking >10 s decreased from 31.9% (30/94) to 13.6% (17/125, P=0.001), and >20 s decreased from 19.1% (18/94) to 4.8% (6/125, P<0.001). The longest duration pre-installation was 120 s, and post-installation 35 s. CONCLUSIONS: This simple, safe, and inexpensive design intervention should be considered as a design standard in all operating theatres to minimise delays in calling for help.

Impact of spinal versus general anaesthesia on perioperative obstructive sleep apnoea severity in patients undergoing hip arthroplasty: a post hoc analysis of two randomised controlled trials.

BACKGROUND: Recommendations suggest favouring regional over general anaesthesia to reduce impact on postoperative sleep apnoea severity, but there is currently no evidence to support this. We compared the impact of general vs spinal anaesthesia on postoperative sleep apnoea severity and assessed the evolution of sleep apnoea severity up to the third postoperative night. METHODS: This post hoc analysis used pooled data from two previous randomised controlled trials in patients undergoing total hip arthroplasty under general or spinal anaesthesia (n=96), without performing a preliminary power analysis. All participants underwent respiratory polygraphy before surgery and on the first and third postoperative nights. The primary outcomes were the supine apnoea-hypopnea index on the first postoperative night and the evolution of the supine apnoea-hypopnea index up to the third postoperative night. Secondary outcomes included the oxygen desaturation index on the first and third postoperative nights. RESULTS: In the general and spinal anaesthesia groups, mean (95% confidence interval) values for the supine apnoea-hypopnoea index on the first postoperative night were 20 (16-25) and 21 (16-26) events h-1 (P=0.82), respectively; corresponding values on the third postoperative night were 34 (22-45) and 35 (20-49) events h-1 (P=0.91). The generalised estimating equations model showed a significant time effect. Secondary outcomes were similar in the two groups. CONCLUSIONS: Use of spinal anaesthesia compared with general anaesthesia was not associated with a reduction in postoperative sleep apnoea severity, which was worse on the third postoperative night. CLINICAL TRIAL REGISTRATION: NCT02717780 and NCT02566226.

Perioperative use of glucagon-like peptide-1 receptor agonists and sodium-glucose cotransporter 2 inhibitors for diabetes mellitus.

Type 2 diabetes mellitus is an increasingly common long-term condition, and suboptimal perioperative glycaemic control can lead to postoperative harms. The advent of new antidiabetic drugs, in particular glucagon-like peptide-1 (GLP-1) receptor agonists and sodium-glucose cotransporter 2 (SGLT2) inhibitors, has enabled perioperative continuation of these medicines, thus avoiding the harms of variable rate i.v. insulin infusions whilst providing glycaemic control. There are differences between medicines regulatory agencies and organisations on how these classes that are most often used to treat diabetes mellitus, (but also in the case of SGLT2 inhibitors chronic kidney disease and heart failure in those without diabetes) should be managed in the perioperative period. In this commentary, we argue that GLP-1 receptor agonists should continue during the perioperative period and that SGLT2 inhibitors should only be omitted the day prior to a planned procedure . The reasons for the differing advice advocated between regulatory agencies and what anaesthetic practitioners should do in the face of continuing uncertainty are discussed.

The effect of perioperative benzodiazepine administration on postoperative nausea and vomiting: a systematic review and meta-analysis of randomised controlled trials.

BACKGROUND: Despite recent systematic reviews suggesting their benefit for postoperative nausea, vomiting, or both (PONV) prevention, benzodiazepines have not been incorporated into guidelines for PONV prophylaxis because of concerns about possible adverse effects. We conducted an updated meta-analysis to inform future practice guidelines. METHODS: We included randomised controlled trials (RCTs) of all languages comparing benzodiazepines with non-benzodiazepine comparators in adults undergoing inpatient surgery. Our outcomes were postoperative nausea, vomiting, or both. We assessed risk of bias for RCTs using the Cochrane Risk of Bias tool. We pooled data using a random-effects model and assessed the quality of evidence for each outcome using the Grading of Recommendations, Assessment, Development and Evaluation (GRADE) approach. RESULTS: We screened 31 413 abstracts and 950 full texts. We included 119 RCTs; 104 were included in quantitative synthesis. Based on moderate certainty evidence, we found that perioperative benzodiazepine administration reduced the incidence of PONV (52 studies, n=5086, relative risk [RR]: 0.77, 95% confidence interval [CI] 0.66-0.89; number needed to treat [NNT] 16; moderate certainty), postoperative nausea (55 studies, n=5916, RR: 0.72, 95% CI 0.62-0.83; NNT 21; moderate certainty), and postoperative vomiting (52 studies, n=5909, RR: 0.74, 95% CI 0.60-0.91; NNT 55; moderate certainty). CONCLUSIONS: Moderate quality evidence shows that perioperative benzodiazepine administration decreases the incidence of PONV. The results of this systematic review and meta-analysis will inform future clinical practice guidelines. SYSTEMATIC REVIEW PROTOCOL: The protocol for this systematic review was pre-registered with PROSPERO International Prospective Register of Systematic Reviews (CRD42022361088) and published in BMJ Open (PMID 31831540).

Pathological findings associated with the updated European Society of Cardiology 2022 guidelines for preoperative cardiac testing: an observational cohort modelling study.

BACKGROUND: In 2022, the European Society of Cardiology updated guidelines for preoperative evaluation. The aims of this study were to quantify: (1) the impact of the updated recommendations on the yield of pathological findings compared with the previous guidelines published in 2014; (2) the impact of preoperative B-type natriuretic peptide (NT-proBNP) use for risk estimation on the yield of pathological findings; and (3) the association between 2022 guideline adherence and outcomes. METHODS: This was a secondary analysis of MET-REPAIR, an international, prospective observational cohort study (NCT03016936). Primary endpoints were reduced ejection fraction (EF<40%), stress-induced ischaemia, and major adverse cardiovascular events (MACE). The explanatory variables were class of recommendations for transthoracic echocardiography (TTE), stress imaging, and guideline adherence. We conducted second-order Monte Carlo simulations and multivariable regression. RESULTS: In total, 15,529 patients (39% female, median age 72 [inter-quartile range: 67-78] yr) were included. The 2022 update changed the recommendation for preoperative TTE in 39.7% patients, and for preoperative stress imaging in 12.9% patients. The update resulted in missing 1 EF <40% every 3 fewer conducted TTE, and in 4 additional stress imaging per 1 additionally detected ischaemia events. For cardiac stress testing, four more investigations were performed for every 1 additionally detected ischaemia episodes. Use of NT-proBNP did not improve the yield of pathological findings. Multivariable regression analysis failed to find an association between adherence to the updated guidelines and MACE. CONCLUSIONS: The 2022 update for preoperative cardiac testing resulted in a relevant increase in tests receiving a stronger recommendation. The updated recommendations for TTE did not improve the yield of pathological cardiac testing.

Challenges and patient outcomes in chronic subdural haematoma at the level of a regional care system A multi-centre, mixed-methods study from the East of England.

BACKGROUND: Chronic subdural haematoma (cSDH) is a common neurosurgical pathology affecting older patients with other health conditions. A significant proportion (up-to 90%) of referrals for surgery in neurosciences units (NSU) come from secondary care. However, the organisation of this care and the experience of patients repatriated to non-specialist centres are currently unclear. OBJECTIVES: This study aimed to clarify patient outcome in non-specialist centres following NSU discharge for cSDH surgery and to understand key system challenges. The study was set within a representative neurosurgical care system in the east of England. DESIGN AND METHODS: We performed a retrospective cohort analysis of patients referred for cSDH surgery. Alongside case record review, patient and staff experience were explored using surveys as well as an interactive c-design workshop. Challenges were identified from thematic analysis of survey responses and triangulated by focussed workshop discussions. RESULTS: Data on 381 patients referred for cSDH surgery from six centres was reviewed. One hundred and fifty-six (41%) patients were repatriated following surgery. Sixty-one (39%) of those repatriated suffered an inpatient complication (new infection, troponin rise or renal injury) following NSU discharge, with 58 requiring institutional discharge or new care. Surveys for staff (n = 42) and patients (n = 209) identified that resourcing, communication, and inter-hospital distance posed care challenges. This was corroborated through workshop discussions with stakeholders from two institutions. CONCLUSIONS: A significant amount of perioperative care for cSDH is delivered outside of specialist centres. Future improvement initiatives must recognise the system-wide nature of delivery and the challenges such an arrangement presents.

Optimal Perioperative Pain Management of the Transgender Patient for Gender Affirming Surgery: A Scoping Review.

INTRODUCTION: As we increasingly encounter transgender patients in the perioperative setting, it is important to be cognizant of appropriate medical management of the transgender patient. There is limited literature on the appropriate perioperative techniques to implement for adequate pain control in the transgender patient presenting for gender affirming procedures. METHODS: In this scoping review, the authors identify publications that address perioperative pain control techniques that can be implemented by the anesthesiologist such as regional anesthesia, multimodal medications, or non-pharmacologic modalities. RESULTS: This scoping review included two retrospective reviews, two case reports, and one letter to the editor. There are no prospective, randomized controlled trials on this topic. The limitations of this scoping review include the limited publications that are available to analyze as this is a growing area of medicine. CONCLUSION: There are numerous variables that may play a factor in the pain experience of the transgender patient including biological factors, psychological and social factors. Techniques that are necessary for comprehensive pain management include pharmacologic, injections, physical therapy, acupuncture, massage, and more. There are limited publications on the comprehensive pain management of the transgender patient; therefore, the authors advocate that as perioperative physicians, anesthesiologists implement comprehensive preemptive analgesia techniques to avoid progression to chronic pain. Clearly more research is necessary to standardize acute pain management techniques in the transgender patient.

Perioperative quality indicators specific to the practice of anesthesia in noncardiac surgery: an umbrella review.

PURPOSE: Improvement in delivery of perioperative care depends on the ability to measure outcomes that can direct meaningful changes in practice. We sought to identify and provide an overview of perioperative quality indicators specific to the practice of anesthesia in noncardiac surgery. SOURCE: We conducted an umbrella review (a systematic review of systematic reviews) according to Joanna Briggs Institute methodology. We included systematic reviews examining perioperative indicators in patients ≥ 18 yr of age undergoing noncardiac surgery. Our primary outcome was any quality indicator specific to anesthesia. Indicators were classified by the Donabedian system and perioperative phase of care. The quality of systematic reviews was assessed using AMSTAR 2 criteria. Level of evidence of quality indicators was stratified by the Oxford Centre for Evidence-Based Medicine Classification. PRINCIPAL FINDINGS: Our search returned 1,475 studies. After removing duplicates and screening of abstracts and full texts, 23 systematic reviews encompassing 3,164 primary studies met our inclusion criteria. There were 330 unique quality indicators. Process indicators were most common (n = 169), followed by outcome (n = 114) and structure indicators (n = 47). Few identified indicators were supported by high-level evidence (45/330, 14%). Level 1 evidence supported indicators of antibiotic prophylaxis (1a), venous thromboembolism prophylaxis (1a), postoperative nausea/vomiting prophylaxis (1b), maintenance of normothermia (1a), and goal-directed fluid therapy (1b). CONCLUSION: This umbrella review highlights the scarcity of perioperative quality indicators that are supported by high quality evidence. Future development of quality indicators and recommendations for outcome measurement should focus on metrics that are supported by level 1 evidence. Potential targets for evidence-based quality-improvement programs in anesthesia are identified herein. STUDY REGISTRATION: PROSPERO (CRD42020164691); first registered 28 April 2020.

RéSUMé: OBJECTIF: L'amélioration de la prestation des soins périopératoires dépend de la capacité de mesurer les résultats qui peuvent orienter des changements significatifs dans la pratique. Nous avons cherché à identifier et à fournir une vue d'ensemble des indicateurs périopératoires de qualité spécifiques à la pratique de l'anesthésie en chirurgie non cardiaque. SOURCES: Nous avons mené une revue d'ensemble (une revue systématique des revues systématiques) selon la méthodologie de l'Institut Joanna Briggs. Nous avons inclus des revues systématiques examinant les indicateurs périopératoires chez les patient·es âgé·es de 18 ans ou plus bénéficiant d'une chirurgie non cardiaque. Notre critère d'évaluation principal était tout indicateur de qualité spécifique à l'anesthésie. Les indicateurs ont été classés en fonction du système de Donabedian et de la phase périopératoire des soins. La qualité des revues systématiques a été évaluée à l'aide des critères AMSTAR 2. Le niveau de donnée probante des indicateurs de qualité a été stratifié selon l'Oxford Centre for Evidence-Based Medicine Classification. CONSTATATIONS PRINCIPALES: Notre recherche a permis de trouver 1475 études. Après avoir éliminé les doublons et examiné les résumés et les textes intégraux, 23 revues systématiques englobant 3164 études primaires ont répondu à nos critères d'inclusion. Il y avait 330 indicateurs de qualité uniques. Les indicateurs de processus étaient les plus courants (n = 169), suivi des indicateurs de résultats (n = 114) et des indicateurs de structure (n = 47). Peu d'indicateurs identifiés étaient étayés par des données probantes de haut niveau (45/330, 14 %). Les données probantes de niveau 1 ont confirmé les indicateurs de l'antibioprophylaxie (1a), de la prophylaxie pour la thromboembolie veineuse (1a), de la prophylaxie postopératoire pour les nausées/vomissements (1b), du maintien de la normothermie (1a) et de la fluidothérapie ciblée (1b). CONCLUSION: Cet examen d'ensemble met en évidence la rareté des indicateurs périopératoires de qualité qui sont étayés par des données probantes de haute qualité. L'élaboration future d'indicateurs de qualité et de recommandations pour la mesure des résultats devrait être axée sur des paramètres étayés par des données probantes de niveau 1. Les cibles potentielles des programmes d'amélioration de la qualité de l'anesthésie fondés sur des données probantes sont identifiées dans le présent manuscrit. ENREGISTREMENT DE L'éTUDE: PROSPERO (CRD42020164691); premier enregistrement le 28 avril 2020.

Accuracy and clinical utility of heart rate variability derived from a wearable heart rate monitor in patients undergoing major abdominal surgery.

Low heart rate variability (HRV) can potentially identify patients at risk of intraoperative hypotension. However, it is unclear whether cheaper, readily accessible consumer heart rate (HR) monitors can provide similar utility to clinical Holter electrocardiograph (ECG) monitors. The objectives of this study were (1) to assess the validity of using the Polar H10 HR monitor as an alternative to a clinical Holter ECG and (2) to test total power (TP) as a predictor of intraoperative hypotension. The primary outcome was the level of agreement between Polar H10 and Holter ECG. Twenty-three patients undergoing major abdominal surgery with general anesthesia had 5-minute HR recordings taken concurrently with both devices during a pre-anesthetic consultation. Agreement between Polar H10 and Holter ECG was compared via Bland-Altman analysis and Lin's Concordance Correlation Coefficient. Patients were divided into groups based on TP < 500 m s 2 and TP > 500 m s 2 . Intraoperative hypotension was defined as MAP < 60 mmHg, systolic blood pressure < 80 mmHg, or 35% decrease in MAP from baseline. There was substantial agreement between Polar H10 and Holter ECG for average R-R interval, TP and other HRV indices. Reduced TP (< 500 ms 2 ) had a high sensitivity (80%) and specificity (100%) in predicting intraoperative hypotension. Patients with reduced TP were significantly more likely to require vasoactive drugs to maintain blood pressure.The substantial agreement between Polar H10 and Holter ECG may justify its use clinically. The use of preoperative recordings of HRV has the potential to become part of routine preoperative assessment as a useful screening tool to predict hemodynamic instability in patients undergoing general anesthesia.

Knowledge-based, computerized, patient clinical decision support system for perioperative pain, nausea and constipation management: a clinical feasibility study.

Opioid administration is particularly challenging in the perioperative period. Computerized-based Clinical Decision Support Systems (CDSS) are a promising innovation that might improve perioperative pain control. We report the development and feasibility validation of a knowledge-based CDSS aiming at optimizing the management of perioperative pain, postoperative nausea and vomiting (PONV), and laxative medications. This novel CDSS uses patient adaptive testing through a smartphone display, literature-based rules, and individual medical prescriptions to produce direct medical advice for the patient user. Our objective was to test the feasibility of the clinical use of our CDSS in the perioperative setting. This was a prospective single arm, single center, cohort study conducted in Strasbourg University Hospital. The primary outcome was the agreement between the recommendation provided by the experimental device and the recommendation provided by study personnel who interpreted the same care algorithm (control). Thirty-seven patients were included in the study of which 30 (81%) used the experimental device. Agreement between these two care recommendations (computer driven vs. clinician driven) was observed in 51 out 54 uses of the device (94.2% [95% CI 85.9-98.4%]). The agreement level had a probability of 86.6% to exceed the 90% clinically relevant agreement threshold. The knowledge-based, patient CDSS we developed was feasible at providing recommendations for the treatment of pain, PONV and constipation in a perioperative clinical setting.Trial registration number & date The study protocol was registered in ClinicalTrial.gov before enrollment began (NCT05707247 on January 26th, 2023).

Human-centered visualization technologies for patient monitoring are the future: a narrative review.

Medical technology innovation has improved patient monitoring in perioperative and intensive care medicine and continuous improvement in the technology is now a central focus in this field. Because data density increases with the number of parameters captured by patient-monitoring devices, its interpretation has become more challenging. Therefore, it is necessary to support clinicians in managing information overload while improving their awareness and understanding about the patient's health status. Patient monitoring has almost exclusively operated on the single-sensor-single-indicator principle-a technology-centered way of presenting data in which specific parameters are measured and displayed individually as separate numbers and waves. An alternative is user-centered medical visualization technology, which integrates multiple pieces of information (e.g., vital signs), derived from multiple sensors into a single indicator-an avatar-based visualization-that is a meaningful representation of the real-world situation. Data are presented as changing shapes, colors, and animation frequencies, which can be perceived, integrated, and interpreted much more efficiently than other formats (e.g., numbers). The beneficial effects of these technologies have been confirmed in computer-based simulation studies; visualization technologies improved clinicians' situation awareness by helping them effectively perceive and verbalize the underlying medical issue, while improving diagnostic confidence and reducing workload. This review presents an overview of the scientific results and the evidence for the validity of these technologies.

Vasopressors to treat postoperative hypotension after adult noncardiac, non-obstetric surgery: a systematic review.

BACKGROUND: Postoperative hypotension is common after major surgery and is associated with patient harm. Vasopressors are commonly used to treat hypotension without clear evidence of benefit. We conducted a systematic review to better understand the use, impact, and rationale for vasopressor administration after noncardiac, non-obstetric surgery in adults. METHODS: We conducted a prospectively registered systematic review. Cochrane CENTRAL, EMBASE, MEDBASE, and MEDLINE were searched for RCTs and cohort studies of adult patients receiving vasopressors after noncardiac, non-obstetric surgery. Study quality was critically appraised by two investigators. Findings from the review were synthesised, but formal meta-analysis was not performed because of significant variability in study populations and outcomes. RESULTS: A total of 3201 articles were screened, of which seven RCTs, two prospective cohort studies, and 15 retrospective cohort studies were included in the analysis (24 in total). One study was graded as high quality, two as moderate quality, and the remaining 21 as low quality. Sixteen studies relied on clinical assessment alone to decide on therapeutic interventions. Vasodilation was the most common suggested physiological disturbance. The median proportion of patients receiving vasopressors was 42% (interquartile range: 11.5-74.7%). Norepinephrine was the most common vasopressor used. CONCLUSIONS: The evidence supporting the use of vasopressors to treat postoperative hypotension is limited. Future research should focus on whether vasodilatation or other physiological disturbance is driving postoperative hypotension to allow rational decision-making.

Long-term disease interactions amongst surgical patients: a population cohort study.

BACKGROUND: The average age of the surgical population continues to increase, as does prevalence of long-term diseases. However, outcomes amongst multi-morbid surgical patients are not well described. METHODS: We included adults undergoing non-obstetric surgical procedures in the English National Health Service between January 2010 and December 2015. Patients could be included multiple times in sequential 90-day procedure spells. Multi-morbidity was defined as presence of two or more long-term diseases identified using a modified Charlson comorbidity index. The primary outcome was 90-day postoperative death. Secondary outcomes included emergency hospital readmission within 90 days. We calculated age- and sex-adjusted odds ratios (OR) with 95% confidence intervals (CI) using logistic regression. We compared the outcomes associated with different disease combinations. RESULTS: We identified 20 193 659 procedure spells among 13 062 715 individuals aged 57 (standard deviation 19) yr. Multi-morbidity was present among 2 577 049 (12.8%) spells with 195 965 deaths (7.6%), compared with 17 616 610 (88.2%) spells without multi-morbidity with 163 529 deaths (0.9%). Multi-morbidity was present in 1 902 859/16 946 808 (11.2%) elective spells, with 57 663 deaths (2.7%, OR 4.9 [95% CI: 4.9-4.9]), and 674 190/3 246 851 (20.7%) non-elective spells, with 138 302 deaths (20.5%, OR 3.0 [95% CI: 3.0-3.1]). Emergency readmission followed 547 399 (22.0%) spells with multi-morbidity compared with 1 255 526 (7.2%) without. Multi-morbid patients accounted for 57 663/114 783 (50.2%) deaths after elective spells, and 138 302/244 711 (56.5%) after non-elective spells. The rate of death varied five-fold from lowest to highest risk disease pairs. CONCLUSION: One in eight patients undergoing surgery have multi-morbidity, accounting for more than half of all postoperative deaths. Disease interactions amongst multi-morbid patients is an important determinant of patient outcome.

Effect of perioperative benzodiazepine use on intraoperative awareness and postoperative delirium: a systematic review and meta-analysis of randomised controlled trials and observational studies.

BACKGROUND: Benzodiazepine use is associated with delirium, and guidelines recommend avoiding them in older and critically ill patients. Their perioperative use remains common because of perceived benefits. METHODS: We searched CENTRAL, MEDLINE, CINAHL, PsycInfo, and Web of Science from inception to June 2021. Pairs of reviewers identified randomised controlled trials and prospective observational studies comparing perioperative use of benzodiazepines with other agents or placebo in patients undergoing surgery. Two reviewers independently abstracted data, which we combined using a random-effects model. Our primary outcomes were delirium, intraoperative awareness, and mortality. RESULTS: We included 34 randomised controlled trials (n=4354) and nine observational studies (n=3309). Observational studies were considered separately. Perioperative benzodiazepines did not increase the risk of delirium (n=1352; risk ratio [RR] 1.43; 95% confidence interval [CI]: 0.9-2.27; I2=72%; P=0.13; very low-quality evidence). Use of benzodiazepines instead of dexmedetomidine did, however, increase the risk of delirium (five studies; n=429; RR 1.83; 95% CI: 1.24-2.72; I2=13%; P=0.002). Perioperative benzodiazepine use decreased the risk of intraoperative awareness (n=2245; RR 0.26; 95% CI: 0.12-0.58; I2=35%; P=0.001; very low-quality evidence). When considering non-events, perioperative benzodiazepine use increased the probability of not having intraoperative awareness (RR 1.07; 95% CI: 1.01-1.13; I2=98%; P=0.03; very low-quality evidence). Mortality was reported by one randomised controlled trial (n=800; RR 0.90; 95% CI: 0.20-3.1; P=0.80; very low quality). CONCLUSIONS: In this systematic review and meta-analysis, perioperative benzodiazepine use did not increase postoperative delirium and decreased intraoperative awareness. Previously observed relationships of benzodiazepine use with delirium could be explained by comparisons with dexmedetomidine. SYSTEMATIC REVIEW PROTOCOL: PROSPERO CRD42019128144.

Perioperative outcome assessment from the perspectives of different stakeholders: need for reconsideration?

Standardised and universal perioperative endpoint reporting are the cornerstone for outcomes assessment, reliable clinical trials, and health services research. The Outcome4medicine initiative recently reported consensus recommendations on how to assess the quality of surgical interventions, proposing a framework for surgical outcome assessment and quality improvement after medical interventions. In the same field, the Standardised Endpoints in Perioperative Medicine - Core Outcome Measures for Perioperative and Anaesthetic Care (StEP-COMPAC) group recently proposed standardised and valid measures of mortality and morbidity, derived from a three-stage Delphi process. Here a core group of the Outcome4medicine conference discusses how these two initiatives are aligned and emphasises the importance of standardised outcome assessment by integrating the perspectives of different stakeholders.

High-dose dexamethasone in low pain responders undergoing total knee arthroplasty: a randomised double-blind trial.

BACKGROUND: Postoperative pain after total knee arthroplasty (TKA) is a continuing problem despite optimised multimodal analgesia. Previous studies have shown preoperative glucocorticoids to reduce postoperative pain, but knowledge about specific doses and effects in specific patient groups is lacking. METHODS: A two-centre, double-blind, two-arm study comparing preoperative dexamethasone (1 mg kg-1vs 0.3 mg kg-1 i.v.) on postoperative pain in 160 planned TKA subjects with low preoperative pain catastrophising and no opioid use. Subjects received multimodal analgesia with paracetamol, cyclooxygenase-2 inhibitors, local anaesthetic infiltration analgesia, and rescue opioids. The primary outcome was percentage of subjects experiencing moderate to severe pain (visual analogue scale >30 mm) upon ambulation at 24 h. Secondary outcomes included pain scores, postoperative inflammation (C-reactive protein), opioid and antiemetics use, and 'Quality of Recovery-15' and 'Opioid-Related Symptom Distress Scale', length of stay, readmissions, and complications up to Day 90. RESULTS: A total of 157 subjects (80 vs 77) were included. No difference was found between groups in the incidence of subjects experiencing visual analogue scale >30 on ambulation 24 h after surgery (56% vs 53%, relative risk =1.07, confidence interval: 0.8-1.4, P=0.65). No differences in other pain outcomes or use of rescue opioids and antiemetics, in Quality of Recovery-15 and Opioid-Related Symptom Distress Scale, length of stay, readmissions, or complications. C-reactive protein values were comparable at 24 h (13 [6-25] mg L-1vs 16 [9-38] mg L-1, P = 0.07), but lower at 48 h (26 [9-52] mg L-1vs 50 [30-72] mg L-1, P<0.01) in the high-dose group. CONCLUSION: Use of 1 mg kg-1vs 0.3 mg kg-1 i.v. dexamethasone in low pain responders after TKA did not improve early postoperative pain or other outcomes in contrast to benefits in a high pain responder population. CLINICAL TRIAL REGISTRATION: NCT03758170 (first registration 29-11-2018).

Celebrating the first centenary of the British Journal of Anaesthesia: a century of discovery and dissemination.

In 2023, the British Journal of Anaesthesia commemorates its first century of publishing innovations in anaesthesia, pain, critical care and perioperative medicine. In honour of this special anniversary we outline a number of exciting initiatives to occur over the course of the year to commemorate this important milestone, and to highlight the many contributions that the British Journal of Anaesthesia has made to patient care, medical research, and medical education in our first 100 years.

Collaboration for Evidence-based Practice and Research in Anaesthesia (CEPRA): A consortium initiative for perioperative research.

Evidence in perioperative care is insufficient. There is an urgent need for large perioperative research programmes, including pragmatic randomised trials, testing daily clinical treatments and unanswered question, thereby providing solid evidence for effects of interventions given to a large and growing number of patients undergoing surgery and anaesthesia. This may be achieved through large collaborations. Collaboration for Evidence-based Practice and Research in Anaesthesia (CEPRA) is a novel collaborative research network founded to pursue evidence-based answers to major clinical questions in perioperative medicine. The aims of CEPRA are to (1) improve clinical treatment and outcomes and optimise the use of resources for patients undergoing anaesthesia and perioperative care, and (2) disseminate results and inform caretakers, patients and relatives, and policymakers of evidence-based treatments in anaesthesia and perioperative medicine. CEPRA is inclusive in its concept. We aim to extend our collaboration with all relevant clinical collaborators and patient associations and representatives. Although initiated in Denmark, CEPRA seeks to develop an international network infrastructure, for example, with other Nordic countries. The work of CEPRA will follow the highest methodological standards. The organisation aims to structure and optimise any element of the research collaboration to reduce economic costs and harness benefits from well-functioning research infrastructure. This includes successive continuation of trials, harmonisation of outcomes, and alignment of data management systems. This paper presents the initiation and visions of the CEPRA network. CEPRA aims to be inclusive, patient-focused, methodologically sound, and to optimise all aspects of research logistics. This will translate into faster research conduct, reliable results, and accelerated clinical implementation of results, thereby benefiting millions of patients whilst being cost and labour-saving.